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Author Shivakumar, K. ♦ Dostal, D. E. ♦ Boheler, K. ♦ Baker, K. M. ♦ Lakatta, E. G.
Source Sree Chitra Tirunal Institute for Medical Sciences & Technology
Content type Text
Publisher American Journal of Physiology-heart and Circulatory Physiology
File Format PDF
Language English
Subject Domain (in DDC) Technology ♦ Medicine & health ♦ Diseases
Subject Domain (in MeSH) Cardiovascular System ♦ Anatomy ♦ Investigative Techniques ♦ Analytical, Diagnostic and Therapeutic Techniques and Equipment
Subject Keyword Cardiology
Abstract The intracardiac ANG II-forming pathway is activated in the senescent myocardium, raising the possibility of enhanced ANG II effects on cardiac fibroblasts. This study established an in vitro model of cultured cardiac fibroblasts from aged rats to examine if the response of these cells to ANG II is modified in the aged heart. Levels of mRNA encoding renin, angiotensinogen, and the AT(1) receptor subtype in cardiac fibroblasts from young adult and senescent rats were quantified by RT-PCR, net collagen production by a hydroxyproline-based assay, and transforming growth factor (TGF)-beta levels using a commercial kit. In cardiac fibroblasts from young adult rats, ANG II significantly enhanced AT(1) mRNA levels, net collagen production, and TGF-beta production. In fibroblasts from the aged myocardium, ANG II downregulated AT(1) mRNA expression, had a less pronounced effect on net collagen production, and had no effect on TGF-beta production. Such age-related modification of the response of cardiac fibroblasts to ANG II may counteract the effects of augmented intracardiac ANG II production in the senescent heart, limiting fibrogenesis.
Education Level UG and PG
Learning Resource Type Article
Educational Framework Medical Council of India (MCI)
Journal American Journal of Physiology-Heart and Circulatory Physiology
Volume Number 284
Issue Number 4